Fix migrate authors query pagination

Author: mattheu

inc/cli/class-migrate-command.php

@@ -92,7 +92,7 @@ public function wp_authors( $args, $assoc_args ) : void {
 			 */
 			$posts = get_posts( [
 				'posts_per_page'      => $posts_per_page,
-				'paged'               => $paged,
+				'paged'               => $dry_run ? $paged : 1,
 				'post_status'         => 'any',
 				'ignore_sticky_posts' => true,
 				'suppress_filters'    => false,
@@ -128,7 +128,9 @@ public function wp_authors( $args, $assoc_args ) : void {
 			WP_CLI::line( sprintf( 'Processed %d posts, pausing for a breath...', $count ) );
 			sleep( 2 );
 
-			$paged++;
+			if ( $dry_run ) {
+				$paged++;
+			}
 		} while ( count( $posts ) );
 
 		if ( true === $dry_run ) {